The present invention relates to a low-pressure mold assembly, and more particularly to a valve assembly for a mold which minimizes the frequency of flushing.
A low pressure molding system provides for the mixing of at least two fluid materials to form a settable mixture which is discharged into a mold cavity to form a finished article. One particular mixture includes three fluid material components which form a matrix having a catalyst, a matrix polymer and a foaming agent. The fluid materials are typically fed from a supply by a delivery or feed assembly which communicates with a mixing head. The fluid materials are mixed by the mixing head and discharged into the mold cavity to form the molded article.
Typically, the mold valve and mix head must be flushed after each cycle to remove remnants of the fluid material components to prevent the remnants from hardening within. This is time consuming and expensive as the flushing fluid must be disposed of after usage.
Accordingly, it is desirable to provide a valve assembly for a low-pressure mold which requires minimum flushing. It is also desirable to minimize the necessity of flushing the mix head between transfer from one mold assembly to the next to decrease the cycle time for production of each finished article.